Most small mammals and upland game birds, such as the ruffed 

 grouse, require a mixture of cover and openings. Maintaining 

 suitable openings is a major management problem in forested areas. 



Waterfowl. — For most waterfowl species, the 

 most critical determinants of abundance are the 

 quantities and qualities of water and wetland habitat 

 that are available. Some species, such as the mallard, 

 demonstrate great adaptability; others, such as can- 

 vasbacks, require more specific conditions. Unlike 

 the management of resident game habitat, mainte- 

 nance or creation of habitat in one area may greatly 

 influence the number of waterfowl in other areas. 



The maintenance and enhancement of breeding, 

 migration, and wintering habitats offer possibilities 

 for maintaining waterfowl resources as well as 

 increasing hunting opportunities. Flooding of hard- 

 wood bottom lands in the Southeast during the fall 

 and winter, either artificially or through natural 

 flooding, significantly increases the habitat base and 

 carrying capacity for waterfowl. 



Return irrigation flows are a vital source of water 

 for migrating and wintering waterfowl, particularly in 

 the arid West. Loss of this water source or increased 

 consumption for industrial and residential uses would 

 have serious impacts on waterfowl. Providing addi- 

 tional water during the dry seasons would signifi- 

 cantly increase the habitat base. Other practices for 

 improving food and cover include mowing, pres- 

 cribed burning, disking, planting, and — on a limited 

 scale — carefully managed livestock grazing. 



The Fish and Wildlife Service administers about 4 

 million acres of migratory bird refuges throughout 

 the four fly ways and another 1.4 million acres of 

 small waterfowl production areas located mostly in 

 the glaciated prairie pothole region. As of 1975, State 

 conservation agencies controlled approximately 5 



million additional acres of land and water of major 

 value to waterfowl, much of which is open to public 

 hunting. About half of the acreage was State-owned 

 and the remainder under lease or other agreement. 

 About 11,000 private waterfowl hunting clubs con- 

 trolled, through leases and ownership, more than 5 

 million acres of waterfowl habitat. Many of these 

 acres provide opportunities to help ensure healthy 

 waterfowl populations through cooperative programs. 

 One notable milestone in the management and 

 protection of waterfowl and other migratory birds is 

 the 1976 Convention Between the United States of 

 America and the Union of Soviet Socialist Republics 

 Concerning the Conservation of Migratory Birds and 

 Their Environment. This Convention goes a step 

 further in the protection of migratory birds than do 

 similar treaties with Canada, Mexico, and Japan. The 

 treaty with the Soviet Union also: 



• generally prohibits disturbance of nesting 

 colonies; 



• agrees that both countries will undertake 

 measures necessary to enhance the habi- 

 tat of migratory birds and will provide 

 immediate warning if pollution or de- 

 struction of habitat occurs or is expected; 

 and 



• calls for special protection of species in 

 danger of extinction. 



Other birds. — As is true for small mammals, the 

 many species of resident and common migrant birds 

 in the Nation have a variety of habitat requirements. 

 In general, the habitat requirements for native non- 

 game birds can be met on forest lands if representa- 

 tive vegetation types, age classes, and forest openings 

 are maintained and interspersed on a management- 

 unit basis. To adequately provide for cavity nesters, 

 some portion must be managed on long rotations 

 and/ or some trees not harvested at all. After timber is 

 harvested, to the extent that is feasible, slash should 

 be left on the ground and not chopped or burned.'*' 



On range lands, the first concerns are to avoid 

 overgrazing and to minimize the trampling of vegeta- 

 tion near water sources. Periodically resting lands 

 from grazing for at least a year is beneficial. Because 

 grasslands have little vertical vegetative structure, 

 bird populations are usually smaller than on forest 

 lands. Maintaining occasional areas in forbs and 

 shrubs and small trees, rather than converting to pure 

 grass, will lead to the greatest variety of species. 



■•^ See separate papers by Zeedyk, W, D., by K. E. Evans, R. F. 

 Buttery, and P. W. Shields, and by J. W. Thomas and others. In 

 Symposium on management of forest and range habitats for non- 

 game birds. Smith, D. R. (Tech. Coord.). Forest Service, Gen, 

 Tech. Rep. WO-1. 343 p. Washington, D.C. 1975. Also see Whit- 

 comb, R. F. and others. Island biogeography and conservation: 

 strategy and limitations. Science 193:1030-1032. 1976. 



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